Helminths of two anuran species, Atelopus spurrelli (Bufonidae) and Dendrobates histrionicus (Dendrobatidae), from Colombia, South America

Two species of anurans from Colombia, South America, Atelopus spurrelli and Dendrobates histrionicus, were examined for helminths. A. spurrelli was found to harbor three species of Nematoda, adults of Cosmocerca podicipinus and larvae of Physocephalus sp. and Porrocaecum sp. D. histrionicus was found to harbor, in addition to C. podicipinus, Physocephalus sp. and Porrocaecum sp. and cystacanths of three species of Acanthocephala: Centrorhynchus sp., Onicola sp. and Polymorphus sp. A. spurrelli and D. histrionicus represent new host records for these helminths.     

猫脑干上涎核节前神经元电活动的观察

在麻醉的32只猫记录了电刺激颌下腺神经支引起的上涎核平均场电位和单位放电。逆行电刺激颌下腺神经支引起的上涎核平均场电位分布在同侧脑干背面闩部头端5.5—8mm处,与过去的组织学结果大致符合。用微电极在上涎核记录了68个对刺激颌下腺神经支有反应的单位,其中33个单位作了碰撞试验。有9个单位符合逆向反应标准,它们是真正的颌下腺节前神经元,逆行反应的潜伏期为14.4±2.5ms,其轴突传导速度为2.9±0.1m/s。其他不符合逆向反应标准的单位,对刺激颌下腺神经支仍能发生反应,估计多为中间神经元。在一部分单位观察了电刺激舌神经或味觉刺激舌引起的反应。根据这些观察对上涎核内存在复杂神经元回路的可能性作了讨论。     

Gastric nematodes of the Paraguayan caiman, Caiman yacare (Alligatoridae).

Examination of the stomach contents of 115 Caiman yacare Daudin, 1802, from Paraguay revealed the presence of the nematodes Brevimulticaecum baylisi (Travassos, 1933), Brevimulticaecum stekhoveni (Baylis, 1947), Contracaecum sp. of Railliet and Henry, 1912, Dujardinascaris paulista (Travassos, 1933), Eustrongylides sp. of Jagerskiold, 1909, Micropleura vazi Travassos, 1933, and Ortleppascaris alata (Baylis, 1947). Nematode prevalence was 28%; greatest species prevalence (14%) was found for B. baylisi. Greatest mean intensity, 25.4, was for Contracaecum sp. All occurrences are new host and distribution records.     

The microanatomy of the compound eye of Munida irrasa (Decapoda: Galatheidae)

The compound eye of Munida irrasa differs in several respects from the typical decapod eye. The proximal pigment is found only in retinula cells. The eccentric cell is extremely large and expanded to fill the interstices of the crystalline tract area; thus, a typical "clear-zone" is absent. Six retinula cells course distally to screen two sides of the crystalline cone. There are approximately 12,500 ommatidia in each compound eye. There are several similarities to the typical decapod eye. Each ommatidium is composed of a typical cornea, corneagenous cells, crystalline cone cells, crystalline cone, crystalline cone tract and eight retinula cells. Distal pigment cells are present and surround the crystalline cone. The distal processes of the retinula cells also contain pigment. The retinula cell processes penetrate the basement membrane as fascicles composed of processes from adjacent retinulae.     

New species of Falcaustra (Nematoda: Kathlaniidae) in Nyctimystes cheesmani (Anura: Hylidae) from Papua New Guinea

Falcaustra batrachiensis n. sp. (Ascaridida, Kathlaniidae) from the large intestine of Nyctimystes cheesmani (Anura, Hylidae) is described and illustrated. Falcaustra batrachiensis represents the fifth Australo-Papuan species assigned to the genus and is distinguished from other Australo-Papuan species by the distribution pattern of the caudal papillae (8 precloacal, 2 adcloacal, 6 postcloacal, and 1 median), length of spicules (1.4-1.6 mm) and presence of pseudosuckers (5 or 6). Nyctimystes cheesmani was found to harbor 7 additional species of Nematoda, adults of Cosmocerca novaeguineae, Maxvachonia ewersi, Meteterakis crombiei, Physalopteroides milnensis, Pseudorictularia dipsarilis, Seuratascaris numidica, larvae in cysts of Abbreviata sp., and 1 species of Acanthocephala, Acanthocephalus bufonis. Nyctimystes cheesmani represents a new host record for each of these helminth species.     

Thubunaea dactyluris Sensu Fabio and Rolas, a synonym of Physalopteroides venancioi (Spirurida, Physalopteridae)

Specimens of Thubunaea dactyluris Karve, 1938 sensu Fabio and Rolas, 1974 from the lizard Ameiva ameiva of Brazil and types of Physalopteroides venancioi (Lent, Freitas, and Proen?a, 1946) from the toad Bufo paracnemis of Paraguay were re-examined. The male caudal papillae and the tooth arrangement demonstrated that these specimens were conspecific and are all assigned to P. venancioi. The occurrence of Physalopteroides dactyluris (Karve, 1938), a nematode parasite of lizards of India and Turkmenistan, is invalidated for Brazil.     

Integumental lesions caused by ectoparasites in a wild population of the side-blotched lizard (Uta stansburiana)

Histopathological effects of ectoparasites on integument were examined for a wild population of the side-blotched lizard Uta stansburiana. These included the trombiculid Neotrombicula californica, the pterygosomatid mite Geckobiella texana; the macronyssid mite Ophionyssus natricis (Macronyssidae) and the ixodid tick Ixodes pacificus. A diffuse inflammatory response occurred at the site of chigger and tick attachment which consisted of histiocyte, heterophil, fibroblast and lymphocyte infiltration that often extended into the dermis. Granuloma formation also was noted. The most prevalent parasite was N. californica which frequently occurred in large aggregations above the eyelids. Ectoparasites were most abundant from February through April.     

New genus, new species of Acanthocephala (Echinorhynchidae) from the Brazilian frog Hylodes phyllodes (Anura: Leptodactylidae)

Anuracanthorhynchus tritaxisentis n. gen., n. sp. from the intestines of the Brazilian frog Hylodes phyllodes (Leptodactylidae) is described and illustrated. Anuracanthorhynchus tritaxisentis n. gen., n. sp., is unique among the echinorhynchid Acanthocephala by possessing a spherical proboscis supporting a small number of hooks of equal size. It is the sixth acanthocephalan species reported from South American anurans.     

Isomer identification by kinetic energy release measurements using the voltage pulsed collision cell technique in mass-analysed ion kinetic energy spectrometry

The voltage pulsing of the collision cell on a mass-analysed ion kinetic energy spectrometer allows simultaneous kinetic energy release measurements for unimolecular (T(V)), collision-induced (TCID(V)) and composite unimolecular and collision-induced (Tcomp(V)) decomposition processes in the time frame of a capillary gas chromatographic peak. The information gained by voltage pulsing sometimes allows more reliable isomer identification than by kinetic energy release measurements made in the non-pulsing mode alone. Presented are T(V), TCID(V) and Tcomp(V), and the ratio of their intensities for a number of isomeric halogenated compounds.